Comparatively loud English supporter (9)
I believe the answer is:
brassiere
'supporter' is the definition.
(a bra gives support to breasts)
'comparatively loud english' is the wordplay.
'comparatively loud' becomes 'brassier' ('brassy' can be a synonym of 'loud').
'english' becomes 'e' (abbreviation).
'brassier'+'e'='BRASSIERE'
(Other definitions for brassiere that I've seen before include "Female undergarment supporter" , "garment" , "support" .)